The use of signs to display messages is extensively used in many forms and for many reasons. Most signs are of a permanent nature as to their location and the messages they display.
There is a need for a portable sign apparatus that permits the ready changing of a displayed message. For example, there have been many incidents where persons with disabled vehicles were assaulted upon leaving the relative safety of their locked vehicle. A portable changeable sign would allow the motorist to call for help without leaving the vehicle.
Similarly, street repair and maintenance by its very nature creates hazards to the motorists and repair crews that could be averted with adequate warning. Traffic accidents create conditions that require the precise awareness by passing motorists of unusual hazards. Flares, cones and flagmen are inadequate for this purpose.
Serious floor hazards (wet floors, drop offs, etc.) and dangers inherent in high risk industrial areas (flammable, explosive, radioactive or otherwise toxic conditions) necessitate explicit and highly obvious or blatant warnings to passersby. There is no portable, changeable sign adapted for warning passersby of such hazards.
Retail stores and wholesale showrooms use conventional signs in their windows to state hours of operation and/or around their products to indicate price savings and other sales information. Presently available electric window signs require connection to permanent electric wiring.
It is thus apparent that a need presently exists for a sign that is self-contained, easily changeable and portable in nature.